Cold crash to achieve pitching temperature


#1

Hi there,

My first brew with the Brewpi.

I am able to cool the wort to no lower than around 29-30 degrees (Celcius) using a counter flow chiller, but wish to ferment at around 19 degrees.

I am using Safale US-05, and want to cold crash the wort from around 30 degrees to about 21 degrees as quickly as possible, and then pitch the yeast.

However, by using beer mode, my chest freezer only cools to about 15 degrees. This does not have the desired effect of quickly reducing the temperature. I would be happier if the freezer temperature cooled a lot more.

How can I achieve this? I thought about using fridge mode but do not want to set it low and forget about it, and ending up with a frozen wort! If I adjust any of the settings, could it have any unintended consequences?


#2

In fact you can see that the fridge setting was too high for my liking, so I plugged the freezer directly to the power point, and the Brewpi wanted to turn the heater on… the direct opposite what I was trying to achieve.


#3

Beer to fridge maximum difference I’d say, looks like you have that set to 6.

A fan in the fridge will also help. Look for a squirrel cage fan.


#4

OK, will look at investing in a fan!

If I set the fridge max difference to say 30, that’s not going to cause any overshoots etc during fermentation?

What I want to do is quickly get the temp to maximum pitching temp, pitch the yeast, then slowly bring the temp down to ideal fermenting temp.


#5

When clipped to the maximum, the integrator is disabled. This prevents overshoot.
I think it is better to keep the maximum, but increase it to 10 or 15. You can also increase Kp to make it reach the maximum faster (and therefore clip more and prevent windup).

If you have a fan in the fridge, the beer will heat up the air more and your fridge temperature will not drop that far anyway.

A small fan is enough: https://www.aliexpress.com/popular/small-blower-fans.html